llvm-project

43d9238a - [RISCV][P-Ext] Prefer pack/ppairo.h over pncvt.h/pncvth.h in shuffle lowering (#227105)

[RISCV][P-Ext] Prefer pack/ppairo.h over pncvt.h/pncvth.h in shuffle lowering (#227105) These have equivalent behavior, but pncvt.h/pncvth.h requires the input to be a register pair. Shuffle lowering doesn't know if the sources came from the same 64-bit value so using pncvt.h/pncvth.h may overconstrain register allocation and require copies. If some hardware has better performance for pncvt.h/pncvth.h we can consider ways to intelligently pick the two alternatives. For now just pick pack/ppairo.h.